A B S T R A C TThe lust 40 years has seen significant evolution of. the synthetic pyrethroids from their relatioelp restricted usage in domestic fly and mosquito control to their adoption in ull major ureus of public heulth pest control. The use of' tl7e synthetic pyrethroids in national and international control campuigns and it7 village leael selj4ielp pest-control schemes fbr major disease uectors such as mosquitoes, tsetse und blackfly is e.uamined. Their successfirl introduction into the urban public health sector for control of' cockroaches, fleas, bedbugs and lice, etc., is reviewed.

The development and properties of the photostable pyre–throids are reviewed with reference to the use of permethrin for the protection of wool. An emulsifiable concentrate formulation (of this insecticide) – Perigen * – has been developed for use as an industrial mothproofer. The compound shows excellent fastness on wool and good biological activity against the major textile pests. The influence of dyebath pH, dyeing auxiliaries and duration of boiling in the dyebath on the application of the insecticide, is discussed. The low residue levels in effluent from dyebaths following application of Perigen are unlikely to pose any hazard during disposal. Application rates are given for Perigen as an insect–proofing agent for yarn destined for carpets and other products.